Why do my CONTOUR lines disappear when I shade my plot using the SHADING function in MATLAB 7.1 (R14SP3)?

I want to label and apply shading to my CONTOUR plot. When I execute the following commands in MATLAB 7.1 (R14SP3), my labels remain, but my contour lines disappear.

[X,Y] = meshgrid(-2:.2:2,-2:.2:3);

Z = X.*exp(-X.^2-Y.^2);

pcolor(X,Y,Z);

caxis([-2 3]);

hold on

[C,h] = contour(X,Y,Z,'k');

clabel(C,h,'FontSize',8,'color','k');

shading interp

Answer 1

[MathWorks Support Team]

The SHADING function controls the color shading of surface and patch graphics objects. The contour lines generated by the CONTOUR function are patch objects. Therefore if the SHADING command is executed after the CONTOUR command, the color of contour lines, which are patch objects gets controlled by the SHADING function.

To workaround this issue, execute the SHADING command, before the CONTOUR command as explained below:

[X,Y] = meshgrid(-2:.2:2,-2:.2:3);

Z = X.*exp(-X.^2-Y.^2);

pcolor(X,Y,Z);

caxis([-2 3]);

shading interp

hold on

[C,h] = contour(X,Y,Z,'k');

clabel(C,h,'FontSize',8,'color','k');